HTTP 407 Proxy Authentication required - The ISA Server requires authorization to fulfill the request. Access to the Web Proxy service is denied. (12209)

I think that you should change the authentication to windows integrated from Configuration-Networks-Internal-Web Proxy tab - authentication button

After that in the HTTP rule that you created to allow internet access you must specify the group of users that are permitted to use the Proxy service

Dimitris

now the internal interface doesnt take any IP, as well as doesnt take any IP from DHCP, and not able to ping anything inside, only outside is working

If this a server why should use dynamic IP addresses? Try to give him a static IP.
In order to be able to ping from the ISA server you should enable the ICMP and specify where the server can ping. By default the ISA blocks all traffic.
Create a rule in the ISA to allow http from the internal to external network. Remember always that ISA blocks all traffic!!

even when i put static it doent ping anything inside, thats why i try dynamic and keep searching for IP and it doesnt take any IP address.
also i added new network card and till doesnt take IP, which it was before.
shall i format the server ???

no you do not have to format the server.
I think that you should understand how the ISA works.
As i told you before by default ISA blocks all traffic, and you have to create rules to permit traffic through ISA.
Also you have to specify the network ranges for the internal (trusted network). Everything that it is not trusted it is the external network.
There is a very good site the isaserver.org that has a lot of information about ISA configuration.

ok, I stopped all the isa server services, and connect the server to the network and still doesnt get the ip, as i need to join it to the domain as well...!!!!!!!!

backup the ISA configuration and try to uninstall the application. See if after that you can get IP address. If not then there is something else and not the ISA

ok, after un installing ISA application the server got IP address, could you send me a link for step by step isa installation or shall i restore the backup... thanks

also where i can download ISA 2004?

if rou search the internet there are many sites with information about isa installation.
If you start the wizard try to be very careful with the internal and external network.
Internal is your LAN and External is whatever is not in your LAN.
When you finish the installation go to the configuration page and select the correct topology depending on the your network infrastructure.

You can always buy the ISA 2004 server or you can download a free 180 trial from microsoft.com

could u send me the link for downloading isa 2004 from microsoft.com as i only can find the service packs..
thanks

thanks got it